Lead alloy



Patented June 24, 1930 UNITED squares- PATENT OFFICE LEAD ALLOY nopmwm Application filed April 11, 1927, ser aino. 182,999, and in Great Britain April 16, 1926.

the resistance of certain types of lead to sulphuric acid corrosion is also considerably improved.

Antimony may also be employed to improve the mechanical properties of lead but 29 approximately twice as much antimony as cadmium is needed in order to produce the same effect, the improvement achieved by the use of antimony extending also to the resistance of certain types of corrosion.

Tin improves the mechanical and corrosion-resisting properties of lead but considerably more tin is required in order to produce the same effect than either cadmium or antimony. Tin, however, increases the resistance of lead to atmospheric and other types of corrosion, particularly acetic acid corrosion. v

The present invention is based upon the observation that the above defects attendant upon the use of pure lead may be eliminated by the addition of other metals to the lead, the resultant alloy being also of greatly increased strengthas compared with lead itself. a

The invention consists in an alloy containing lead and cadmium, and one o both of the metals tin and antimony in theproportions up to 5 per cent. and 3 per cent. respectively. I

The invention further consists in a lead alloy containing cadmiuln up to 2 per. cent., antimony up to 3 per cent. and tin up to 5 per cent. 3

The-invention still further consists in a 56 lead alloy containing two or more of the him the metals cadmium, antimony and tin in which the mechanical properties are improved by heating to a temperature exceeding 150 .0. followed by quenching in water, or any other form of rapid cooling.

The invention also consists in other details hereinafter described or illustrated.

In carrying our invention into'efiect we produce an alloy of lead and cadmium containing other metals as hereinbefore stated and we have found that the advantages of the various metals can be combined so that the lead cadmium alloy used in conjunctionwith tin gives an alloy which possesses the improved mechanical properties imparted by the cadmium together with the characteristic resistance to corrosion imparted by the tin, while similarly antimony alloys show improved mechancial and corrosion-resistmg properties as compared with alloys in which antimony is not employed. A quaternary alloy may be similarly produced to comproperties of the various constituent metals. I I

The ternary and quaternary alloys produced in accordance with the invention are susceptible 'to heat treatment and if heated to a temperatureexceeding 150 C. and then quenched in water or rapldly cooled in any other way the hardness and tensile strengt increase with time up to a maximum value depending upon the proportions of alloying metals used. Further, such ternary and quaternary alloys show a marked freedom from oxidation during melting while greater uniformity in composition is possible than with the binary alloys.

We have found that when producing lead alloys for use asc'able sheathing, pipe and sheeting very satisfactory. results may be I desire to secure by Let-" cent respectively and not less than 0.10 per cent of cadmium and 0.25 per cent of tin.

2. A lead allo con 0.10 per cent to2percentc 'umand .25 percentto 5 5percentmetalfromthegroup of tin and antimony.

8. A cable sheathing formed from a lead alloy containing from 0.10 per cent to 2 per cent cadmium and 0.25 per cent to 5 per cent metal from the group consisting of tin and antimony.

In testimony whereof we have signed our names to this cification.

' SYD Y BECKINSALE. HERBERT'WATERHOUSE. 

